Tennis practice machine



TENNIS PRACTICE MACHINE Filed Oct. 26, 1934 2 Sheets-Sheet 1 5 0 20 ea u.Fdzzzanaoff. Jermq Oct. 13, 1936. E. H. SERRANO TENNIS PRACTICE MACHINEFiled Oct. 26, 1954 2 Sheets-Sheet 2 Patented Get. 13, 1933 PATENTOFFICE TENNIS PRACTICE MACHINE Edmundo H. Serrano, St. Louis, Mo.,assignor to Luella J. Serrano, St. Louis, Mo.

Application October 26, 1934, Serial No. 750,219

5 Claims.

This invention relates to tennis practice machines adapted to project aseries of tennis balls at a player in varied trajectories and angles.

1 The primary object of this invention is to provide a device of theabove mentioned character which is entirely automatic and which requiresno attention whatsoever once the machine has been placed in operation.

A further object of this invention is to pro vide a machine of the abovementioned character having a wheeled frame to which is pivotally secureda ball carrying frame having a striker adapted to project balls indifferent heights.

'A' still further object of this invention is to provide a device of theabove mentioned character having a ball striking member provided withtwo or more striking faces which will project a tennis ball in differenthorizontal angles.

A still further object of this invention is to provide means for feedingtennis balls at spaced intervals to a support directly in the path ofthe striking device and said means includes a novel arrangementcomprising a receptacle having a series of chutes for receiving ballsand novel means for allowing the dispensing of one ball at a time fromsaid chutes.

A further object of this invention is to provide a support upon whichthe tennis balls are fed so as to be positioned in the path of thestriking device and said support is provided with a plurality ofsurfaces adapted to cause irregularities in the travel of the ball afterbeing struck by the striking member.

A further object of this invention is to provide a striking member for amachine of the above mentioned character, the movements of which willsimulate the action of a human player.

A still further object of this invention is to provide a device of theabove mentioned character controlled by an automatic switch whereby apredetermined number of balls may be projected after which the machinewill be completely turned off and will become inoperative.

A still further object of this invention is to provide a rotary brush ina tennis ball receptacle adapted to re-knap and clean the balls prior totheir release upon the ball support in the path of the striking member.

A still further object of this invention is to provide means forregulating the force of the blow struck by the striking element wherebytennis balls may be projected varied distances.

7 Other objects and advantages of the'invention will become apparentduring the coarse of the following description forming a part of thespecification and in which,

Figure 1 is a top plan view of the device embodying this inventionillustrating the tennis ball receptacle and its circularly arrangedchutes with respect to the striking element;

Figure 2 is a vertical front plan view partly in section illustratingthe tennis ball receptacle in detail and further showing its relationwith respect to the striking element and the other cooperative parts;

Figure 3 it a side plan view of the device embodying this inventionillustrating the striker arm and the details of the operatingconstruction along with other associated elements;

' Figure 4 is a transverse cross sectional view illustrating the drivearrangement and gearing for operating the several parts of the machine;

Figure 5 is a top plan view of the striking device showing the samegreatly enlarged for the purpose of illustrating the details ofconstruction;

Figure 6 is a side plan view of the striking member further illustratingthe gut strings with respect to the playing surface;

Figure 7 is an end plan view showing the manner in which the gut stringsare spaced and held in position;

Figure 8 is a fragmentary side view of a portion of the supporting frameand the adjustable connection between the tilting mechanism and the samecarried by the frame plates.

In the drawings, wherein for the purpose of illustrating the inventionand wherein like rei erence characters will be employed to designatelike parts throughout the same, the reference character ID willgenerally be employed to designate a wheeled frame formed of angle barsspaced and braced by cross bars H. Through the wheeled frame 10 extendsan axle l2 on the ends of which are casters or rollers I3. The oppositeend of the wheeled frame In is provided with a foot 14 whereby saidframe may be levelled with respect to the ground.

A pair of handle bars i5 is pivoted to the wheeled frame as at l6 andthe upper ends of the handle bars l5 are connected by a horizontal barll so that the handle bars I5 may be moved outwardly so that the stopsl8'will engage the wheel frame Ill and form a means of moving themachine from different positions to desired locations.

Extending upwardly from the wheeled frame ID are opposite supports l9riveted to the wheeled frame as at 20 and having the upper ends thereofconverging inwardly and connected as at 2|. Pivotally mounted betweenthe vertical frame members l9 as at 22 is a frame structure comprisingangle bars 23 joined at their intermediate portions by plates 24 and thelower end of the frame is provided with a floor 25 to which is bolted anelectric motor 26 having an armature shaft 2! upon which are mountedpulleys 28 and 29.

Journalled in bearings 38 carried by a pair of opposite frame plates 24as shown in Figure 4 is a shaft 3| on one end of which is fixed a collar32 having a grooved pulley 33 so that a belt 34 may be trained thereoverand around one of the armature shaft pulleys 28. The intermediateportion of the shaft 3| is provided with a worm 35 adapted to drive ashaft 36 at right angles to the shaft 3|. One end of the shaft 36 isjournalled in an anti-friction bearing 31 secured in one of the frameplates 24 while the opposite end as at 38 is received in a bore 39formed in a stub shaft 48 which is rotatably mounted in anti-frictionbearings 4| mounted in the opposite frame plate 24. Rigidly secured toone end of the stub shaft 48 is a striker arm 42 having a strikingmember on the outer end which will be hereinafter more fully described.

Power is imparted to the rotary shaft 36 by means of a worm wheel 43rigidly secured thereon and meshing with the worm 35 on the shaft 3|.Carried by the worm wheel 43 is a collar 44 having a set screw 45 forrigidly securing the worm wheel 43 and collar 44 to the shaft 36 andsecured to the collar 44 as at 46 is a disk 41 to which is pivotallysecured a dog 48 held in place by a threaded stub shaft 49 locked by anut 56.

Rigidly secured to the stub shaft is a drum 5| to which is attached anotched wheel 52 adapted to be engaged by the pawl 48 therebyestablishing a rigid connection between the shaft 36 with the stub shaft48 at intervals. Anti-friction bearings 53 may be mounted between thedrum 5| and the pawl carrying disk 41 and said anti-friction bearingsare similar to the anti-friction bearings 4! whereby free and easyrotation may be provided.

The construction above described will effect the drive of the shaft 36through the medium of the worm 35 and worm wheel 43 to cause therotation of the pawl carrying disk 41 which pawl 48 will normally beurged toward the notched wheel 52 by means of a retention device 54which will cause the clutching of the disk 41 with the toothed wheel 52and will result in the drive of the stub shaft 40 through the drum 5|.Attached to the drum 5| are straps 55 and 56 and interposed in thestraps 55 and 56 are rubber straps 51 and 58. The rubber strap 58 hasconnected thereto a strap 59 which passes over a pulley 60 secured in asheave 6| passing through the floor 25 of the frame and the opposite endof the strap 59 extends through an opening 62 in a pivoted lever 53having one of its ends connected as at 64 to one of the frame members 23While the opposite end is provided with a detent 65 adapted to engage anotched segment piece 66 secured also to one of the vertical framepieces 23. By connecting the opposite end of the rubber strap 51 withthe strap-59 it will be obvious that the tension of both straps 51 and58 may be regulated. to place the drum 5| under different, degrees oftension.

When the pawl 48 is received within the notch in the notched wheel 52,the drum 5| will be rotated against the tension of the rubber straps 51and 58 as the straps 55 and 55 will wind upon the drum 5| and elongatethe rubber straps 51 and 58. After the drum 5| has been rotated apredetermined portion of a revolution, the pawl 48 may be released fromthe notched wheel 52 by engaging a roller 6'! rotatably mounted betweenthe arms 68, which arms are secured to one of the frame plates 24. Thestriking arm 42 is operated upon reverse rotation of the drum 5| aftersaid drum has been rotated against the tension of the straps 55 and 56and elastic elements 51 and 58 and-after the pawl 48 has been releasedby the trip member secured to the frame in the path of the pawl 48.

Secured to the stub shaft 40 is a pulley 69 having a V-shaped groove 19in which is positioned a friction member having one of its ends as at 12anchored to a bracket 73, suitably fastened to one of the side frameplate members 24 by means of a nut and bolt 15. The bracket 13 may bespaced from the frame plates 24 by means of a washer l6 and the oppositeend of the friction clamp may be secured to a similar bracket 71 alsosecured to the frame member 24 by means of a nut and bolt 18 and asshown in Figure 3, a coil spring 19 is adapted to surround a bolt 89 towhich the opposite end of the friction element H is connected so thatone end of the coil springs will engage the bracket Ti and the oppositeend will engage a disk 8| on said bolt 88 whereby the friction band Hmay be placed under tension in order to brake the rotation of the stubshaft 46 without shock and place the same under friction. I

Carried by the upper end of the vertical frame member 23 is a receptacle83 having a sloping bottom 84 around which is positioned a shell 85 forthe purpose of strengthening the construction. Arranged around the innercircumference of the receptacle 83 are chutes or guides 86 adapted tocontain tennis balls in stacked relation and said balls are adapted torest upon an annular shelf 81 to limit the downward travel of the tennisballs within the chutes 86. The chutes 86 are carried by a disk 88secured to the upper end of a hollow shaft 89, the lower end of which isjournalledin a frame piece 90' and is provided with a worm wheel 9|adapted to mesh with a worm 92 rigidly secured to the drive shaft 36.The annular shelf 8'! is provided with openings of sufficient diameteras at 94 and 94a for the passage of tennis balls whereby one ball at atime may be passed beneath the annular shelf 87 and into a chamber 95 asshown by dotted lines in Figure 2, where they are dispensed through anopening 960. onto the support 91. Slidably secured to the shelf 8'! isan adjustable plate 941) adapted to alternately cover the openings 94and 94a and said plate may be adjusted by means of a thumb screw 940. Ifthe plate 941) is positioned over the opening 94, the tennis balls willtravel a complete revolution in the chamber 95 whereby the ball may bereknapped by the rotary brush. Otherwise the ball dropping through theopening 94 will be immediately dispensed. The disks 88 are provided withten vertical chutes 86 each of which is adapted to'contain'six tennisballs in such a manner that the ballsmay be dispensed one at a timethrough the opening formed in the sloping floor 84 of the receptacle sothat they may pass upon theirotary support 91 and be-guided thereon bythe guideway 99. The. tennis balls are held in position upon the support91 by means of an arm I secured to the receptacle 83 by means of thebracket IOI held in place by rivets or other fastening elements I02.

It will be noted that the rotary support 91' is mounted on a shaft I03suitably secured to the crosspiece I having the ends thereof secured tothe vertical framem'ember 23. Said rotary support 91 is provided withthree faces I06, one of which has one depression where the ball comes torest and the striking arm projects it in one and the same direction, thesecond face has two depressions I20 and I2I so positioned that the ballwill come to rest in either one of the depressions by chance and thestriking arm' will project the ball in two directions to either cornerof the tennis court. The third face I06 is smooth and level the ballcoming to rest anywhere by chance and when struck by angled face of gutII1 willproject the ball at different directions.

The reversible striking element mounted on the end of the arm 42comprises as shown in Figtires 5, 6 and '1, a shaft I01 securedto thefree end of the striking element 42 by means of a nut I08 and providedon one end of the shaft I01 is a block I09 having a hub IIO forattachment to the end of the shaft I01 as by means of a screw IIIpassing through the block I09 and having its threaded end screwed in theend of shaft I01, block I09 is moved away from block H2 therebyincreasing tension of tennis strings II1. At the opposite end of theshaft I01 there is also provided a similar block having a hub II3loosely mounted upon shaft I01 so that a coil spring H4 may normallyurge the hub II3 away from the opposite block I09 this to take up thestretch in the strings and the give in a tennis racket frame at the timeof impact with the ball. Rigidly secured upon the shaft I01 at theintermediate portion thereof is a guide block II5 drilled as at IIB forreceiving a series of gut strings 1 which are trained around the guideblocks I09 and H2. The gut strings II1 extend through slots H8 formed inblocks I09 and H2 in the end walls as clearly shown in Figures 5, 6 and7.

It will be noted that the striking element is adapted to pass directlyabove the tennis ball support 91 and Top Spin can be imparted to thetennis ball when striking face is tilted to strike the tennis ball abovecenter and Undercut Spin can be imparted to the tennis ball whenstriking face is tilted to strike the tennis ball below center.

Extending through the hollow shaft 89 is a driven shaft I25 on the upperend of which is rigidly secured a disk I20 provided with a circularbrush I21. The periphery of the brush is adapted to contact the tennisball falling within the chamber 95 for the purpose of cleaning andre-knapping the balls after they have been used and worn smooth inregular play.

The lower end of shaft I25 is provided with a pulley I250. around whichis trained as shown in Figure 4 a belt I29 extending over sheaves I30mounted on axle I3I carried by a bracket I32 rigidly secured to one offrame plates 24 by a nut and bolt I33. The endless belt I29 passesdownwardly and is trained over the armature pulley 29 mounted on thearmature of the motor 25. Disk I28 attached to shaft 89 is provided withfive slots I34 carrying rollers I35 which are adapted to engage a camportion I30 formed intermediate the ends of a pivoted lever I31, one endof which is pivoted to a bracket I38 secured to one side frame platemember 24 by screws I39 and a pivot' pin I40 extending through thebracket I38 and through one end of the lever I31 and is'held in place bya cotter pin MI. The free end of the pivoted lever I31 extends through aslot in the opposite frame plate member 24 and is provided with a linkI42 having one of its ends received in an opening I43 and its oppositeend pivotally secured in the upper portion of the frame member 2I as atI44, and capable of being adjusted by means of the thumb screwconnection I44a. as shown in Figures 2, 3 and 8.

As shown in Figure 8, the link I42 is detached from the connection I43and from the upper end of the support 2I whereby the frame 24 may beheld stationary by passing the thumb screw through the supporting framea sufficient distance to engage the series of apertures I42a formed in aplate I421) secured to the frame plates 24. When the thumb screw isengaged with the plate M21) as above described, the link I42 will be inthe position shown in Figure 8 and when it is desired to tilt the frameat every other shot the link I42 is connected to the end of the cam barI31 as at I43 by means of the thumb screw I44a thereby making itnecessary to withdraw the thumb screw as shown in Figure 8 and with thesame connect lever I31 at I43 to link I42 which is attached to frame I9.Three different tilting angles are possible by connecting thumb screw inthree separate holes in link I42.

As disk I28 rotates, the lever I31 is rocked on its pivot I40which'causes the swinging frame 23 to be rocked on its pivot 22 withrespect to the stationary frame I9 whereby tennis balls may be projectedalternately in high or low trajectories.

Automatic means is provided for stopping the motor 26 after apredetermined number of balls have been projected and said meanscomprises a cam I50 mounted upon one end of the shaft 30 adapted toengage a pivoted dog I5I which may be secured to the frame piece 24 andmay have its end held into engagement with a ratchet wheel I52 securedto a stub shaft I53 mounted on a suitable bracket I54. The opposite endof the stub shaft I53 is provided with a hand knob I55 having a pointerI56 adapted to register with the graduations on a dial attached to sideframe piece 24. One end of a spring I51 is presented to the ratchetwheel I52 in a frictional manner to' hold the wheel in position after ithas been stepped a single notch by the pivoted dog I5I. The spring I51is connected to one of the frame plates 24 as at I59 and has itsopposite end encircling the ratchet wheel I52 and is connected to thepivoted dog I5I for normally holding the pivoted dog into engagementwith the teeth on the ratchet wheel I52. A stud is adapted to be securedto one of the radial faces of the ratchet wheel I52 and said stud mayengage the arm of a snap switch which may be in a suitable circuit. Theswitch is not shown but any form of conventional snap switch may beprovided having a pivoted lever sufficiently long enough to be engagedby the stud carried upon the ratchet wheel I52. By adjusting the pointerI56 to the graduations on the frame plate 24 (not shown) saidgraduations may be in the terms of a number of balls projected, whichsetting will bring the stud on the ratchet wheel I52 into position sothat after a predetermined number of balls have been shot and the shaft36 has been rotated a predetermined number of times to cause the cam Ito step the ratchet up to the desired number of balls projected the studprovided on the ratchet wheel will engage theswitch arm and break thecircuit through the power supply and motor 26. The motor 26 effectsrotation of the shaft 3| by means of the belt and pulley connectionbetween the pulley 28 of the motor and the pulley 33 on the shaft 3 I,rotation of the shaft 3| being transmitted by the worm and worm wheeldevices to the disk 4'! that carries the dog 48 for rotation. of thedrum 5| that effects rotation of the stub shaft 40 carrying the strikerarm 42. The striker arm 42 is moved in a counter-clockwise directionfrom the position shown in'Figure'3 by action of the motor drive andduring such movement, the tension devices 51 and 58 have the tensionthereon increased by movement of the strap members 55 and 56 so thatwhen the dog 48 is released from its engagement with the drum 5|, thespring devices 51 and 58 effect a sudden clockwise movement of thestriker arm 52 for impinging the ball for the delivery thereof.

It is to be understood that the form of the invention herewith shown anddescribed is to be taken as the preferred embodiment of the same andthat various changes in the shape, size and arrangement of parts may beresorted to without departing from the spirit and scope of the inventionas claimed.

1. A ball projecting machine comprising a base member, a swinging framecarried by the base frame, a receptacle secured to the upper end of theswinging frame adapted to receive a plurality of balls in stackedrelation, means for dispensing said balls singly, a support forreceiving said balls having a plurality of curved surfaces and differentdepressions, and means for projecting said balls after they have beendispensed upon said support.

2. A ball projecting machine comprising a base frame, a swinging framecarried by the base frame, a receptacle secured tothe upper end of theswinging frame, means in said receptacle for supporting a plurality ofballs in stacked relation, means for dispensing said balls singly, asupport for receiving said balls having arcuately curved surfaces, astriking arm for engaging said balls for projecting the same in one ordifferent directions, means for operating the strikirrg arm and meansfor swinging said frame with respect to the base frame. wherebydifferent trajectories may be imparted to said balls.

3. Av ball projecting machine comprising a base frame, a swinging framecarried by the base frame, means for dispensing a plurality of ballscarried by the upper end of the swinging frame, a support for receivingsaid balls, a striking arm for engaging the balls and projecting thesame in one. orv different directions, means for operating the swingingarm comprising a driven shaft, a motor for driving said shaft, a clutchconnecting said shaft to the swinging arm, and means for tripping saidclutc 4. A ball striking machine having a striking arm, means foroperating the striking arm comprising a motor driven shaft, a clutch forconnecting the motor driven shaft to the striking arm, means for placingthe striking arm under tension and means for tripping said clutch.

5. A ball striking machine having a striking arm having a ball engagingmember on the free end thereof which is strung with regular gut stringsone surface a flat plane for projecting the balls in one direction andthe opposite surface with two planes at angles to each other forprojecting the ball in different directions.

EDMUNDO H. SERRANO.

